I have removed and replaced a similar model on one of my 2004's. If you are doing a total pull and replace, it is not that hard but I do not know your background skills.
The outside flange is sealed to the side of the camper like any door, window or cargo hole that uses putty tape. You will need new sealing tape when you put it back on.
You will have to deal with the gas line and that fitting can be hard to get at and threaded back on true. You have to do a gas leak test after you install it.
The electrical part of hook up is not that bad. There is power and a T stat connection
The duct hoses have a twist on flange adapter that goes from hose to the furnace round hole.
The hardest part is separating the seal to the side of the camper and the LP gas line connection due to the spot it is located in. hard to get to.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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